Method for determining characteristic spectrum of micro-nano sensing structure micro-particle pollutants

Abstract

The application discloses a kind of micro-nano sensing structure micro-particle pollutant characteristic spectrum determination methods, belong to micro-nano sensing structure reliability detection technical field, comprising: in micro-nano sensing structure design and manufacture micro-particle pollution simulation structure, by test means in micro-nano sensing structure introduce information known micro-particle pollution simulation;Drive the micro-nano sensing structure to move, and by test circuit collection obtains the electrical signal when the micro-nano sensing structure moves;Make the micro-particle pollution simulation move, until the micro-particle pollution simulation collides on the micro-nano sensing structure that is moving;Analysis and processing the electrical signal before and after the micro-nano sensing structure collides with the micro-particle pollution simulation, obtains the micro-nano sensing structure micro-particle pollutant collision characteristic spectrum.The application is by artificial introduction controllable parameter micro-particle pollution simulation and analyzes collision electrical signal characteristics, solves the problem that existing visual method cannot accurately identify the micro-particle pollutant characteristics inside the micro-nano sensing structure that has been packaged, realizes the non-invasive dynamic characteristic analysis to micro-particle pollutant shape, size and quantity.

Description

Technical Field

[0001] This invention belongs to the field of reliability testing technology for micro-nano sensing structures, and specifically relates to a method for determining the characteristic spectrum of microparticle contaminants in micro-nano sensing structures. Background Technology

[0002] Micro- and nano-sensing structures have advantages such as miniaturization, low cost, and low power consumption, and have been widely used in consumer electronics, communications, navigation, and other fields. As the core structure of micro- and nano-sensing structures, they are usually movable structures. However, micro-particle contaminants generated during processing and use can easily cause the movable structure of the micro- and nano-sensing structure to jam and fail.

[0003] Microparticles (such as silicon chips, photoresist residues, and dust) in micro-nano sensing structures are mostly in the submicron to tens of micrometer range. Because micro-nano sensing structures have three-dimensional movable structures, large specific surface areas, and narrow gaps (such as comb teeth, cantilever beams, and cavities), the gaps are mostly in the micrometer range, which can easily lead to the following failures: (1) Particles get stuck in the gaps of movable structures (such as comb teeth, hinges, and thin films), resulting in obstructed movement, jamming, or abnormal travel. (2) Electrical short circuits / leakage, conductive particles (metal chips, doped silicon particles) fall between electrodes / wires, causing local short circuits, leakage, or breakdown; particles contaminate the dielectric layer, causing increased leakage current and insulation degradation.

[0004] Microparticle contaminant failure is a very important type of failure in micro / nano sensing structures. When it is initially determined that the failure of micro / nano sensor products is caused by microparticle contaminants through some methods, two problems exist: (1) there is currently no effective means to confirm that the failure is caused by microparticle contaminants; (2) there is currently no effective means to clarify the information of microparticle contaminants, including their shape, size, and quantity. The reason for these two problems is that there is currently no characteristic spectrum of microparticle contaminants for micro / nano sensing structures, which greatly affects the research on this type of reliability problem.

[0005] Therefore, in the failure problem of micro / nano sensing structures, there are no effective means for detecting microparticle contaminants, either in terms of detection methods or information analysis. To further investigate the reliability of microparticle contaminant-induced failures in micro / nano sensing structures, it is essential to develop methods for determining the characteristic spectra of microparticle contaminants in these structures. Summary of the Invention

[0006] The main objective of this invention is to overcome the shortcomings and deficiencies of existing technologies and provide a method for determining the characteristic spectrum of microparticle contaminants in micro / nano sensing structures. By analyzing the electrical signals of the micro / nano sensing structure before and after colliding with the microparticle contaminant simulant, the collision characteristic spectrum of the microparticle contaminant in the micro / nano sensing structure can be obtained. This method can identify information such as the size, shape, and quantity of microparticle contaminants in the micro / nano sensing structure, and conduct more comprehensive and accurate research on the failure problems caused by microparticle contaminants in micro / nano sensing structures. It can be used for failure analysis, screening, and quality improvement of micro / nano sensor products.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] This invention provides a method for detecting microparticle contaminants using micro / nano sensing structures, comprising the following steps:

[0009] Design micro / nano sensing structures with moving parts;

[0010] The micro-nano sensing structure incorporates a micro-particulate contaminant mimicry structure.

[0011] Micro-nano sensor structure chips are fabricated and packaged to obtain micro-nano sensor structure samples.

[0012] Through experimental methods, the designed micro-particulate pollutant simulant structure was dropped into the micro-nano sensing structure, thereby introducing the information-knowable micro-particulate pollutant simulant into the micro-nano sensing structure.

[0013] The micro-nano sensing structure sample is driven to move, and the electrical signal of the micro-nano sensing structure during movement is acquired by the test circuit.

[0014] The microparticle pollution simulator is moved until it collides with the moving micro / nano sensing structure.

[0015] Analyze and process the electrical signals of the micro / nano sensing structure before and after collision with the microparticle contaminant simulant;

[0016] The collision characteristic spectrum of microparticle pollutants in the micro / nano sensing structure was obtained.

[0017] As a preferred technical solution, the micro-nano sensing structure is a comb-type capacitor structure with resonant moving parts.

[0018] As a preferred technical solution, the microparticle pollution simulant is a microparticle structure with a preset shape, size and quantity, designed and fabricated by microfabrication process during the fabrication stage of the micro-nano sensing structure.

[0019] As a preferred technical solution, obtaining the collision feature spectrum of microparticle pollutants in the micro-nano sensing structure includes: introducing microparticle pollutant simulants with the same shape and size but different numbers for comparative experiments, collecting electrical signals before and after the collision and performing comparative analysis to obtain the collision feature spectrum of microparticle pollutants corresponding to different numbers in the micro-nano sensing structure.

[0020] As a preferred technical solution, obtaining the collision feature spectrum of the microparticle contaminants in the micro / nano sensing structure includes:

[0021] Comparative experiments were conducted using microparticle contaminants with the same shape and quantity but different sizes. Electrical signals were collected before and after the collisions and compared and analyzed to obtain the collision characteristic spectra of microparticle contaminants corresponding to different sizes of micro-nano sensing structures.

[0022] 6. As a preferred technical solution, obtaining the collision characteristic spectrum of microparticle pollutants in the micro / nano sensing structure includes:

[0023] Comparative experiments were conducted using microparticle contaminants of the same size and quantity but different shapes. Electrical signals were collected before and after the collisions and compared and analyzed to obtain the collision characteristic spectra of microparticle contaminants corresponding to different shapes in micro-nano sensing structures.

[0024] As a preferred technical solution, driving the micro-nano sensing structure sample to move includes driving the micro-nano sensing structure to resonate near the resonant frequency of the micro-nano sensing structure.

[0025] As a preferred technical solution, the method of driving the micro / nano sensing structure to resonate is by mechanical impact or electrical drive.

[0026] As a preferred technical solution, the movement of the microparticle pollution simulator includes moving the microparticle pollution simulator by means of vibration until it collides with the moving micro / nano sensing structure.

[0027] As a preferred technical solution, the method further includes: based on the obtained collision characteristic spectrum information of microparticle pollutants in micro-nano sensing structures, analyzing the quantity, shape, and size of microparticle pollutants in other micro-nano sensing structures.

[0028] The technical solution of the present invention has the following advantages and technical effects:

[0029] This invention effectively solves the technical problem that existing visual methods cannot accurately identify the characteristics of microparticle contaminants inside encapsulated micro / nano sensing structures by artificially introducing microparticle contaminants with precisely controllable shape, size, and quantity into micro / nano sensing structures and then analyzing the electrical signals from collisions between the micro / nano sensing structure and the microparticle contaminants during movement. Because this invention uses electrical signal analysis to obtain collision feature spectrum information, it achieves non-invasive detection of microparticle contaminant characteristics inside encapsulated micro / nano sensing structures without opening the structure or visual observation, greatly expanding the applicability and convenience of microparticle contaminant detection.

[0030] Meanwhile, this invention, through comparative experiments using microparticle contamination simulants with different parameter combinations, obtained collision characteristic spectra of microparticle contaminants with varying quantities, sizes, and shapes. It established a systematic correspondence between the characteristic parameters of microparticle contaminants and the characteristics of collision signals, filling a gap in existing technologies for dynamic collision characteristic analysis of microparticle contaminants. The establishment of this collision characteristic spectrum provides a reliable characteristic reference database for failure analysis and product screening of micro / nano sensor products, making the identification of unknown microparticle contaminants in other micro / nano sensor products a feasible foundation.

[0031] Furthermore, this invention utilizes the characteristic of micro / nano sensing structures moving near their resonant frequencies to acquire collision electrical signals, making collision events exhibit significant identifiable features in the electrical signals and improving the sensitivity and accuracy of collision signal detection. The design of using vibration to move microparticle contaminants until they collide with the resonantly moving micro / nano sensing structure ensures the repeatability and controllability of collision events, providing a guarantee for the stable acquisition of collision feature spectra. The application of the obtained collision feature spectrum information to identify microparticle contaminants in other micro / nano sensing structures further extends the technological achievements of this invention to the field of improving the quality and reliability design of micro / nano sensor products, providing strong technical support for the quality control and reliability improvement of micro / nano sensor products. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a flowchart of the method for determining the characteristic spectrum of microparticle pollutants in micro / nano sensing structures according to the present invention;

[0034] Figure 2The micro-nano sensing structure of the present invention has a micro-particle pollution simulant (red dashed box in the figure) (the left side is a fixed structure and the right side is a movable structure). Detailed Implementation

[0035] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative effort are within the scope of protection of the present application.

[0036] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0037] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0038] This invention addresses the reliability research needs of microparticle contaminants in micro / nano sensing structures. Based on the characteristics of micro / nano sensing structures, it proposes a method for determining the characteristic spectrum of microparticle contaminants in these structures. Microparticle contaminants are inevitably generated during the fabrication and packaging of micro / nano sensing structures. These contaminants, moving freely within the structure, collide with movable parts, causing instantaneous changes in the structure's motion state. These changes can be captured and recorded through characteristic changes in electrical signals. Based on this physical principle, this invention first introduces microparticle contaminant simulants with precisely controllable shape, size, and quantity into the micro / nano sensing structure, establishing a collision signal reference under known parameter conditions. Then, it collects the electrical signals when the micro / nano sensing structure collides with the microparticle contaminant simulants, analyzes and processes the signal characteristic states before and after the collision, and thus obtains the collision characteristic spectrum information of microparticle contaminants in micro / nano sensing structures of different shapes, sizes, and quantities. (See attached diagram) Figure 1 As shown, the implementation process of the method of the present invention is carried out sequentially according to the following steps S1 to S8, as follows:

[0039] Step S1: Design a micro / nano sensing structure with moving parts;

[0040] As attached Figure 2 As shown, a micro / nano sensing structure with moving parts is first designed; in this embodiment, a comb-type capacitor structure is adopted. The comb-type capacitor structure is a common movable structure form in the field of micro / nano sensing structures. It consists of fixed and movable comb teeth arranged alternately. The fixed comb teeth are fixed to the substrate, while the movable comb teeth are suspended above the substrate by an elastic support structure and can reciprocate along the comb tooth direction, forming a comb-type capacitor between the fixed and movable comb teeth. When a driving signal is applied to the driving end of the comb-type capacitor structure, the movable comb teeth reciprocate along the comb tooth direction under the action of the electric field force, forming a resonant motion. The comb-type capacitor structure has a definite resonant frequency, and when driven near its resonant frequency, it can generate significant resonant motion with a large amplitude and stable motion state, which is beneficial for the feature acquisition and identification of collision electrical signals. Another important characteristic of the comb-type capacitive structure is that its motion state can be directly converted into an electrical signal output through changes in the comb-tooth capacitance. When the movable comb tooth moves along the comb tooth direction, the overlap area between the fixed comb tooth and the movable comb tooth changes, resulting in a change in the comb-tooth capacitance value. This change in capacitance value can be converted into an electrical signal output through a test circuit, making the real-time acquisition of motion information of the micro / nano sensing structure convenient and highly sensitive. In specific implementations, the design of the micro / nano sensing structure with comb-type capacitive structure needs to consider the selection of the resonant frequency. The selection of the resonant frequency should ensure that when driven near this frequency, the motion amplitude of the micro / nano sensing structure is large enough, and the impact of collision events on the electrical signal is significant enough to facilitate the differentiation and extraction of electrical signal characteristics before and after the collision. In this embodiment, the resonant frequency of the micro / nano sensing structure with comb-type capacitive structure is designed to be around 10kHz.

[0041] Step S2: A micro-particle pollutant simulant structure is designed into the micro-nano sensing structure;

[0042] The shape, size, and quantity of the microparticle contamination simulants are precisely controllable parameters. The design principle of the microparticle contamination simulants is to ensure the accuracy and repeatability of their parameter information, so that the collision characteristic spectra obtained from multiple experiments under the same parameter conditions are consistent and comparable. In practice, the microparticle contamination simulants are introduced during the fabrication stage of the micro / nano sensing structure. Microfabrication processes are used to design and fabricate microparticle structures with specific shapes, sizes, and quantities near the moving parts of the micro / nano sensing structure. These microparticle structures are used as microparticle contamination simulants in subsequent collision experiments. The precise control capabilities of the microfabrication process ensure the accuracy and consistency of the shape, size, and quantity parameters of each microparticle contamination simulant, providing a reliable foundation for the systematic establishment of collision characteristic spectra.

[0043] Step S3: Through experimental means, the designed micro-particulate pollutant simulant structure is dropped into the micro-nano sensing structure, thereby introducing the information-knowable micro-particulate pollutant simulant into the micro-nano sensing structure.

[0044] To systematically obtain the collision feature spectra corresponding to different parameters, this embodiment designed three sets of comparative sample experiments:

[0045] The first set of samples is a quantity comparison structure, introducing microparticle contaminants with the same shape and size but different quantities: the first type of microparticle contaminant is square in shape, 1μm×1μm in size, and there is 1 of it; the second type of microparticle contaminant is square in shape, 1μm×1μm in size, and there are 10 of it; the third type of microparticle contaminant is square in shape, 1μm×1μm in size, and there are 100 of it. This set of comparison structures is used to establish the correspondence between quantity and collision characteristic spectrum.

[0046] The second set of samples consisted of size comparison structures, introducing microparticle contaminants of the same shape and quantity but different sizes: the first type of microparticle contaminant was square in shape, 1 μm × 1 μm in size, and numbered 10; the second type of microparticle contaminant was square in shape, 5 μm × 5 μm in size, and numbered 10; the third type of microparticle contaminant was square in shape, 10 μm × 10 μm in size, and numbered 10. This set of comparison structures was used to establish the correspondence between size and collision characteristic spectra.

[0047] The third group of samples is a shape comparison structure, introducing microparticle contamination simulants of the same size and number but different shapes: the first type of microparticle contamination simulant is square, 5μm × 5μm in size, and there are 10 of them; the second type of microparticle contamination simulant is circular, with a diameter of 5μm, and there are 10 of them; the third type of microparticle contamination simulant is triangular, with a side length of 5μm, and there are 10 of them; the fourth type of microparticle contamination simulant is rectangular, with a size of 1μm × 10μm, and there are 10 of them. These four shapes of microparticle contamination simulants have different geometric forms while maintaining similar equivalent sizes. The square microparticle contamination simulants have a regular, symmetrical shape; the circular microparticle contamination simulants have a smooth shape without sharp edges; the triangular microparticle contamination simulants have sharp edges; and the rectangular microparticle contamination simulants have an elongated, asymmetrical shape. This set of comparison structures is used to establish the correspondence between shape and collision feature spectrum.

[0048] Step S4: Fabricate and package the micro / nano sensor structure chip;

[0049] After completing the design of the micro / nano sensing structure comb-type capacitor structure and the microparticle contamination simulator, the next step is to fabricate and package the micro / nano sensing structure chip to obtain a micro / nano sensing structure sample. The fabrication process employs microfabrication techniques, including photolithography, etching, and thin film deposition, to fabricate the designed comb-type capacitor structure and microparticle contamination simulator on a silicon substrate. The photolithography step involves coating the silicon substrate with photoresist and then exposing and developing it using a mask to transfer the patterns of the designed comb-type capacitor structure and microparticle contamination simulator onto the photoresist layer. The etching step etches the silicon substrate or thin film layer according to the pattern of the photoresist layer, forming components such as the fixed comb teeth, movable comb teeth, and elastic support structure of the comb-type capacitor structure, as well as the microparticle structure of the microparticle contamination simulator. The thin film deposition step is used to deposit structural layers, sacrificial layers, and other thin film materials on the silicon substrate, providing a material basis for subsequent fabrication. The packaging process encapsulates the fabricated micro / nano sensor chip within a housing, ensuring that both the moving parts of the micro / nano sensor and the microparticle contamination simulator are within a sealed internal space. After packaging, the microparticle contamination simulator is sealed inside the micro / nano sensor structure. In subsequent collision tests, the microparticle contamination simulator can move freely within the housing and collide with the moving comb teeth of the micro / nano sensor structure.

[0050] Step S45: Drive the micro / nano sensing structure to move and acquire electrical signals;

[0051] Driving the micro / nano sensing structure to move includes driving the micro / nano sensing structure to resonate near its resonant frequency, and acquiring the electrical signal during the movement of the micro / nano sensing structure through a test circuit. The method of driving the micro / nano sensing structure to resonate is either mechanical impact or electrical actuation.

[0052] When using mechanical impact, the micro / nano sensing structure sample is mounted on a mechanical impact platform, with the impact direction aligned with the comb tooth movement direction. The mechanical impact test is initiated, causing the comb teeth to move and impact a pre-designed microparticle contamination simulator, allowing the simulator to acquire an initial motion state within the micro / nano sensing structure. The advantage of mechanical impact is the large impact force, enabling the movable parts of the micro / nano sensing structure to achieve a large amplitude and velocity of movement in a single event, while also giving the microparticle contamination simulator a large initial kinetic energy, which is beneficial for subsequent collision events. When using electrical actuation, an electrical signal with a frequency close to the resonant frequency is applied to the driving end of the comb tooth capacitive structure, causing the movable parts of the comb tooth to continuously resonate under the action of the electric field. The advantage of electrical actuation is that the driving signal is controllable, allowing precise adjustment of the driving frequency and amplitude, making the motion state of the micro / nano sensing structure adjustable and repeatable. In practical experiments, mechanical impact is often used to induce initial motion in microparticle contaminants and to initiate initial motion in the movable parts of micro / nano sensing structures. Electrical actuation, on the other hand, is often used to maintain continuous and stable resonant motion near the resonant frequency of the micro / nano sensing structure for signal acquisition. The two actuation methods can be flexibly selected or combined according to the actual experimental conditions and objectives. In this embodiment, the micro / nano sensing structure is driven to resonate near 10kHz. The electrical signal, containing characteristic information such as the amplitude and frequency of motion of the movable comb teeth of the micro / nano sensing structure, is acquired by a test circuit.

[0053] When the micro / nano sensing structure is driven to move near its resonant frequency, the movement amplitude is large and the motion state is stable. When a microparticle contaminant collides with the micro / nano sensing structure in resonant motion, the impact of the collision event on the electrical signal is more significant, facilitating the extraction and comparison of electrical signal characteristics before and after the collision. In the resonant motion state, the movable comb teeth of the micro / nano sensing structure reciprocate with a large amplitude. When the microparticle contaminant collides with the movable comb teeth, it causes an instantaneous disturbance in the comb teeth's motion state. This disturbance manifests as a sudden change in the amplitude of the electrical signal or a shift in frequency characteristics, constituting a identifiable feature of the collision event in the electrical signal.

[0054] Step S6: Move the microparticle contamination simulator until it collides with the moving micro / nano sensing structure;

[0055] The movement of the microparticle contamination simulator includes using vibration to move the simulator until it collides with a moving micro / nano sensing structure. Simultaneously with the resonant motion of the micro / nano sensing structure, mechanical vibration or other means are used to induce movement in the microparticle contamination simulator encapsulated within the micro / nano sensing structure. The simulator moves randomly under vibration until it collides with a movable component of the resonant micro / nano sensing structure. Specifically, the vibration method involves applying external mechanical vibration excitation to the micro / nano sensing structure sample. This excitation creates a corresponding vibration environment inside the micro / nano sensing structure's encapsulation shell, causing the microparticle contamination simulator to move under inertial forces within this environment. Because the microparticle contamination simulator is small in size and mass, even a small vibration excitation can induce significant movement. The simulator moves randomly within the vibration environment until it collides with the movable comb teeth of the resonant micro / nano sensing structure. This method of moving the microparticle contaminant through vibration ensures that the occurrence of collision events is controllable and repeatable. By adjusting the intensity and duration of the vibration excitation, the frequency and timing of collision events can be controlled, thus providing a guarantee for the stable acquisition of collision characteristic spectra.

[0056] Step S7: Analyze and process the electrical signal characteristics before and after the collision;

[0057] After a micro / nano sensing structure collides with a microparticle contaminant simulating a moving object, the electrical signals of the micro / nano sensing structure before and after the collision are analyzed and processed. The analysis and processing methods for the electrical signals include both time-domain analysis and frequency-domain analysis.

[0058] Time-domain analysis methods focus on the abrupt amplitude changes of electrical signals before and after a collision. By detecting instantaneous jumps in signal amplitude, the timing of the collision event is identified, and time-domain characteristic parameters of the collision event are extracted, such as the amplitude change at the moment of collision and the duration of the collision event. The advantage of time-domain analysis methods is that they can accurately pinpoint the timing of the collision event, facilitating the distinction between the electrical signal segments before and after the collision, and providing a time reference for subsequent frequency-domain analysis.

[0059] Frequency domain analysis focuses on the characteristic changes of electrical signals in the frequency dimension before and after a collision. By performing frequency domain transformations on the electrical signals before and after the collision, frequency domain characteristic curves before and after the collision are obtained. The differences between the two frequency domain characteristic curves are compared to extract the frequency domain characteristic parameters of the collision event. Specifically, the frequency domain analysis method involves performing Fourier transforms and other frequency domain transformations on the acquired time-domain electrical signals to obtain the amplitude distribution curve of the electrical signals in the frequency dimension. This amplitude distribution curve has a peak characteristic near the resonant frequency of the micro / nano sensing structure. The occurrence of a collision event causes changes in the amplitude, position, or shape of this peak characteristic, and these changes constitute the identifiable characteristics of the collision event in the frequency domain. The amplitude distribution curves of the electrical signals before and after the collision show significant differences near the resonant frequency. The amplitude distribution curve after the collision exhibits changes such as amplitude attenuation or frequency shift compared to before the collision. The specific form and degree of these changes are closely related to the shape, size, and quantity parameters of the microparticle contaminants in the collision. It is this parameter correlation that provides the physical basis for establishing the collision characteristic spectrum. The extraction of frequency domain characteristic parameters includes amplitude variation, frequency shift, and spectral shape variation near the resonant frequency. These parameters constitute the core elements of the collision characteristic spectrum.

[0060] Step S8: Obtain the collision feature spectrum corresponding to different parameters;

[0061] Obtaining the collision feature spectrum of microparticle pollutants in the micro / nano sensing structure includes obtaining the collision feature spectra corresponding to microparticle pollutant simulants of different quantities, sizes, and shapes. The specific implementation process is as follows:

[0062] Experiments were conducted on the first group of samples: Square-shaped microparticle contaminants measuring 1 μm × 1 μm were introduced in quantities of 1, 10, and 100. Three micro / nano sensing structure samples were mounted on a mechanical impact stage, with the impact direction aligned with the comb tooth movement direction. The mechanical impact test was initiated, causing the comb teeth to move and impact the microparticle contaminants, inducing initial motion in the microparticle contaminants. Then, the micro / nano sensing structures were driven to resonate near 10 kHz, and electrical signals informing the motion of the micro / nano sensing structures were acquired through a test circuit. Simultaneously, mechanical vibration was used to move the introduced microparticle contaminants until they collided with the micro / nano sensing structures in resonant motion. The electrical signals before and after the collision were analyzed and processed, and frequency domain characteristic parameters were extracted. By comparing the characteristic differences of the electrical signals before and after the collisions of 1, 10, and 100 microparticle contaminants, it was found that the frequency domain characteristics of the electrical signals generated by the collisions of different numbers of microparticle contaminants exhibited systematic differences; the greater the number of microparticles, the more significant the impact of the collision event on the amplitude characteristics near the resonant frequency. The amplitude change caused by the collision of a single microparticle pollutant simulant is small, while the amplitude change caused by the collision of 100 microparticle pollutant simulants is large. Among the three, there is a systematic law that the degree of influence increases with the number of particles. Thus, the collision characteristic spectrum of microparticle pollutants for micro-nano sensing structures corresponding to different numbers of particles can be obtained.

[0063] The second group of samples was tested: ten square-shaped microparticle contaminants with dimensions of 1μm×1μm, 5μm×5μm, and 10μm×10μm were introduced. The above collision test procedure was repeated: the microparticle contaminants were brought into an initial motion state through mechanical impact, and the micro / nano sensing structure was driven to resonate near 10kHz to collect electrical signals. The microparticle contaminants were then vibrated to collide with the moving micro / nano sensing structure, and the characteristics of the electrical signals before and after the collision were analyzed. By comparing and analyzing the differences in the characteristics of the electrical signals before and after the collision of the three different sized microparticle contaminants, it can be found that the frequency domain characteristics of the electrical signals generated by the collision of microparticle contaminants of different sizes also have systematic differences. The larger the size, the greater the disturbance of the movable comb motion state of the micro / nano sensing structure by the collision of a single microparticle contaminant, and the more significant the impact of the collision event on the amplitude characteristics near the resonant frequency. The amplitude changes caused by collisions of microparticle pollutants with a size of 1μm×1μm are small, while the amplitude changes caused by collisions of microparticle pollutants with a size of 10μm×10μm are large. This shows a systematic law that the degree of influence increases with the size, thereby obtaining the collision characteristic spectrum of microparticle pollutants for micro-nano sensing structures with different sizes.

[0064] The third group of samples was tested: ten microparticle contaminants were introduced, with shapes of square (5μm×5μm), circular (5μm diameter), triangular (5μm side length), and rectangular (1μm×10μm). The above collision test procedure was repeated, and the electrical signal characteristics before and after the collision were analyzed. When the microparticle contaminants of different shapes collided with the movable comb teeth of the micro / nano sensing structure, the transmission mode of the collision force and the characteristic mode of the collision disturbance also differed due to the different contact surface morphology and collision angle. Square microparticle contaminants have a regular, symmetrical shape, resulting in a larger contact area with the comb teeth during collisions and a more uniform transmission of collision force. Circular microparticle contaminants have a smooth, rounded shape, resulting in a gentler transmission of collision force through an arc-shaped contact surface. Triangular microparticle contaminants have sharp edges, resulting in a concentrated transmission of collision force through a smaller contact area and more intense collision disturbances. Rectangular microparticle contaminants have an asymmetrical, elongated shape, where the contact area and collision angle depend on the collision direction, leading to diverse modes of force transmission. These shape differences are reflected in the frequency domain characteristics of the electrical signals before and after collisions. The characteristic spectra of the electrical signals generated by collisions of microparticle contaminants of different shapes exhibit distinguishable differences, thus allowing us to obtain the collision characteristic spectra of microparticle contaminants corresponding to different shapes of micro / nano sensing structures.

[0065] Step S9: Identify particulate contaminants in other micro / nano sensing structures based on collision feature spectrum information;

[0066] After obtaining collision characteristic spectra of microparticle contaminants in micro / nano sensing structures of varying quantities, sizes, and shapes, this spectral information can be used as a reference database. This database contains a systematic correspondence between the characteristics of various parameters of microparticle contaminants and the frequency domain characteristics of collision electrical signals. For failed micro / nano sensor products with suspected microparticle contaminants, the swept-frequency collision curve of the failed product is first obtained. This is achieved by sweeping the frequency within the resonant frequency range of the failed product while simultaneously acquiring the electrical signals during its movement. Frequency domain analysis is then used to obtain the amplitude distribution characteristic curve of the failed product near the resonant frequency. This swept-frequency collision curve is then compared with the established collision characteristic spectrum information. By comparing the amplitude variation characteristics of the swept-frequency collision curve with the characteristic spectrum patterns corresponding to different quantities, sizes, and shapes in the collision characteristic spectrum, it is possible to identify which type of collision characteristic spectrum best matches the swept-frequency collision curve, thereby revealing information such as the quantity, shape, and size of microparticle contaminants inside the failed micro / nano sensor product sample. This collision feature spectrum-based identification method eliminates the need for unpacking and observing the micro / nano sensor structure, enabling effective determination of particulate contaminant information in packaged micro / nano sensor products. It can be applied to failure analysis and product screening of micro / nano sensor products, and can support improvements in product quality and reliability design. For example, in the factory screening stage of micro / nano sensor products, by performing frequency sweep collision curve detection and comparing it with a collision feature spectrum database, products containing internal particulate contaminants with contaminant parameters reaching the threshold affecting product reliability can be quickly identified, preventing unqualified products from entering the market. In the failure analysis stage of micro / nano sensor products, by comparing the frequency sweep collision curve of failed products with a collision feature spectrum database, it can be determined whether the failure was caused by particulate contaminant collisions, and further, the specific parameter characteristics of the particulate contaminants can be determined, providing targeted guidance for product design and process improvement.

[0067] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0068] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for detecting particulate pollutants using micro / nano sensing structures, characterized in that, Includes the following steps: Design micro / nano sensing structures with moving parts; The micro-nano sensing structure incorporates a micro-particulate contaminant mimicry structure. Micro-nano sensor structure chips are fabricated and packaged to obtain micro-nano sensor structure samples. Through experimental methods, the designed micro-particulate pollutant simulant structure was dropped into the micro-nano sensing structure, thereby introducing the information-knowable micro-particulate pollutant simulant into the micro-nano sensing structure. The micro-nano sensing structure sample is driven to move, and the electrical signal of the micro-nano sensing structure during movement is acquired by the test circuit. The microparticle pollution simulator is moved until it collides with the moving micro / nano sensing structure. Analyze and process the electrical signals of the micro / nano sensing structure before and after collision with the microparticle contaminant simulant; The collision characteristic spectrum of microparticle pollutants in the micro / nano sensing structure was obtained.

2. The method for determining the characteristic spectrum of microparticle pollutants in micro / nano sensing structures according to claim 1, characterized in that, The micro / nano sensing structure is a comb-type capacitor structure with resonant moving parts.

3. The method for determining the characteristic spectrum of microparticle pollutants in micro / nano sensing structures according to claim 1, characterized in that, The microparticle pollution simulant is a microparticle structure with a preset shape, size, and quantity, designed and fabricated through microfabrication technology during the fabrication stage of the micro / nano sensing structure.

4. The method for determining the characteristic spectrum of microparticle pollutants in micro / nano sensing structures according to claim 3, characterized in that, The process of obtaining the collision feature spectrum of microparticle pollutants in the micro / nano sensing structure includes: introducing microparticle pollutant simulants with the same shape and size but different quantities for comparative experiments, collecting electrical signals before and after the collision and performing comparative analysis to obtain the collision feature spectrum of microparticle pollutants corresponding to different quantities in the micro / nano sensing structure.

5. The method for determining the characteristic spectrum of microparticle pollutants in micro / nano sensing structures according to claim 3, characterized in that, Obtaining the collision feature spectrum of the microparticle contaminants in the micro / nano sensing structure includes: Comparative experiments were conducted using microparticle contaminants with the same shape and quantity but different sizes. Electrical signals were collected before and after the collisions and compared and analyzed to obtain the collision characteristic spectra of microparticle contaminants corresponding to different sizes of micro-nano sensing structures.

6. The method for determining the characteristic spectrum of microparticle pollutants in micro / nano sensing structures according to claim 3, characterized in that, Obtaining the collision feature spectrum of the microparticle contaminants in the micro / nano sensing structure includes: Comparative experiments were conducted using microparticle contaminants of the same size and quantity but different shapes. Electrical signals were collected before and after the collisions and compared and analyzed to obtain the collision characteristic spectra of microparticle contaminants corresponding to different shapes in micro-nano sensing structures.

7. The method for determining the characteristic spectrum of microparticle pollutants in micro / nano sensing structures according to claim 1, characterized in that, The method of driving the micro-nano sensing structure sample to move includes driving the micro-nano sensing structure to resonate near the resonant frequency of the micro-nano sensing structure.

8. The method for determining the characteristic spectrum of microparticle pollutants in micro / nano sensing structures according to claim 7, characterized in that, The method of driving the micro / nano sensing structure to resonate is by mechanical impact or electrical drive.

9. The method for determining the characteristic spectrum of microparticle pollutants in micro / nano sensing structures according to claim 1, characterized in that, The movement of the microparticle pollution simulator includes moving the microparticle pollution simulator by means of vibration until it collides with the moving micro / nano sensing structure.

10. The method for determining the characteristic spectrum of microparticle pollutants in micro / nano sensing structures according to claim 1, characterized in that, The method further includes: based on the obtained collision characteristic spectrum information of microparticle pollutants in micro-nano sensing structures, identifying the quantity, shape, and size of microparticle pollutants in other micro-nano sensing structures.

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